Hey gang, i have a 1990 12 Valve cummins. ITs all stock, unknown miles, non inter-cooled. The thing wont start, its puffing black smoke like crazy. At one time the injection pump had been off the truck. I was told the injection timing is off. Any help on getting back to where it needs to be would be awesome! Its been killing me and the guy who has been working on it.

Thanks

Chris

 

take the oil fill off from the timing cover then rotate the engine over by hand and find tdc with the timing pin then you should beable to with a flash light shine it in the oil fill hole and look at where the cam and pump gear meet the ''00'' on the cam should be lined up with the ''e'' on pump thats timed stock

 

I talked to the guy today, he said that was done but still no luck. He is gonna go get the pump bench tested over the next few days to see whats going on with it. Maybe the internal timing is bad?

Chris

 

Black smoke indicates some sort of combustion and that it's a fuel laden mixture.

Start with the absolute basics.
Check for intake air blockage, like a bad filter, something in the aircleaner, etc.

I had a buddy who got pranked once, someone (found out who) stuffed a large rag, with some foam wrapped inside, into the air intake on one of his trucks and it would not fire off after the first attempt to start.
It fired, ran for a few seconds, then died, all it would do after that was smoke black when cranked, but nothing else.
Once we figured it out, it lit right off.
Took me 30 minutes of head scratching and troubleshooting it, pulled the aircleaner hose off and there was the rag stuffed about midway down the intake hose.

Needless to say someone got a real buttchewing on that one.

Mark.

 

The Intake after the turbo is off. Could it be before the turbo?

Chris

 

If it's pulling air at all, then it should run, given that the timing is right and there is no other issue.
It will still run without the turbo hooked up.

Mark.

 

I think there might be something wrong with the injection pump at this point.

 

If the pump has been off, there's a possibility the key that the gear slot rides over was tipped out of it's slot in the pump shaft.
This can screw the timing up AND have the gear marks line up like normal.

The key sometimes ends up in the geartrain, which is bad news.

Mark.

 

Hey guys, a little update on the truck. Took everything apart timing chain cover etc. Truck is on TDC and all marks are lined up on how they should be. Still no start. Looks like its time for a new injection pump. Here is the question which pump should i get? It has VP44 pump, can i up grade to a P7100 pump? IS they any place you guys recommend to get a pump/ Please advise!!!

Chris

 

i think you mean ve pump. this pump was used from 89-93.